Can't make/receive calls but texts and mobile data works and with full bar of signal

[Jimwel]

1. Model Name: Zenfone 9
2. Firmware Version: Android 13 WW_33.0804.2060.142
3. Rooted or not: Not rooted
4. Frequency of Occurrence: Everytime since it started happening

For some reason, my phone suddenly can't make or receive calls. It worked fine for the last 7 months since I bought my phone (late Oct. 2022) but suddenly had this problem lately which started happening around the previous 2 weeks. The weird thing is that I actually have a full bar of signal and I can send/receive text messages just fine and use my mobile data on one of my sims (I use a dual sim and I use one of the sims exclusively for mobile data. However, I'm assuming mobile data works for the other sim as well). I'm from the Philippines so the service providers I use for my dual sim are Globe Prepaid and GOMO (for mobile data).
I've already tested the sims on another working phone, and calls work perfectly so It can't be the sim, but rather the phone itself. I already tried factory resetting the phone and even tried to make calls while volte+wifi call are on/off, to no avail. 

[dilla-]

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[Julius_Victor]

I have the same issue. Incoming / Outgoing calls are not working but mobile data and text are. I flashed my device to its basic firmware (stock firmware) and it worked. I did incremental updates and did phone call tests, everything was working until I updated to firmware version WW_33.0804.2060.142. I tried to update it again to the latest version available which is ".2060.165" and it never fixed the issue. I guess I have to re-flash my device and do incremental updates again only up until before ".2060.142" and I hope ASUS can fix this ASAP. I am starting to regret that I bought this phone as even my camera Gimbal sensors stopped working and camera functionality is extremely intermittent.

I live here in the Philippines and I thought it was just a phone carrier issue, but seeing all your posts and assuming you all live in different countries, I can conclude that his is a firmware issue.

[Jimwel]

I did suspect it was a firmware issue as well but unfortunately I didn't know how to test it as I've never flashed a phone before and a bit hesistant to try to. With your reply, I might just try to check if it would work. Mind sharing any helpful links?

Also, now that you've mentioned it, I just noticed the gimbal is also acting weird on mine as well. Camera and gimbal works fine (i can see the camera lens physically moving) but the circle+dot indicator seems to be broken on mine. The dot just stays in the center instead of moving when the camera moves.

[Julius_Victor]

The only reason I flashed my device to stock ROM is because I bought this online and this came all the way from Taiwan. Because of this, I can't take advantage of the warranty as it only applies to where I bought this. Also, I do not have the specific links anymore as I have read and reviewed several articles just to understand how to flash my device. I do not recommend this to anyone as I may held liable if you brick your device and it becomes unsuable. Also by doing this, you may lose your warranty, so be careful.

If you are still curious on how to flash your device, you can do it at your own risk. Just to give you a bit of an idea, I installed drivers for ADB and Fastbootd, enabled Developer mode on my device, andbought and downloaded the stock firmware from WW-AI2202-32.2040.2040.23-MR2-2208-M2.13.33.19-ASUS_1.1.1-user-20220916.zip | Rom Developers

[Jimwel]

Same case for me actually. Also bought mine online so I can't really take advantage of the warranty.  I definitely will try to research a lot more before I actually try to flash mine though.

Mind if I ask as well since I figured this might be a question a bit too niche to be googled easily, but how did you "incrementally update"? I imagine if you try to check for updates it will just give you the latest one, or does it not?